package org.eclipse.jetty.websocket;
   
   import java.io.IOException;
   import java.util.HashMap;
   import java.util.Map;
   
   import org.eclipse.jetty.io.Buffer;
   import org.eclipse.jetty.util.QuotedStringTokenizer;
   import org.eclipse.jetty.websocket.WebSocketParser.FrameHandler;
  
  public class AbstractExtension implements Extension
  {
      private static final int[] __mask = { -1, 0x04, 0x02, 0x01};
      private final String _name;
      private final Map<String,String> _parameters=new HashMap<String, String>();
      private FrameHandler _inbound;
      private WebSocketGenerator _outbound;
      private WebSocket.FrameConnection _connection;
      
      public AbstractExtension(String name)
      {
          _name = name;
      }
      
      public WebSocket.FrameConnection getConnection()
      {
          return _connection;
      }
  
      public boolean init(Map<String, String> parameters)
      {
          _parameters.putAll(parameters);
          return true;
      }
      
      public String getInitParameter(String name)
      {
          return _parameters.get(name);
      }
  
      public String getInitParameter(String name,String dft)
      {
          if (!_parameters.containsKey(name))
              return dft;
          return _parameters.get(name);
      }
  
      public int getInitParameter(String name, int dft)
      {
          String v=_parameters.get(name);
          if (v==null)
              return dft;
          return Integer.valueOf(v);
      }
      
      
      public void bind(WebSocket.FrameConnection connection, FrameHandler incoming, WebSocketGenerator outgoing)
      {
          _connection=connection;
          _inbound=incoming;
          _outbound=outgoing;
      }
  
      public String getName()
      {
          return _name;
      }
  
      public String getParameterizedName()
      {
          StringBuilder name = new StringBuilder();
          name.append(_name);
          for (String param : _parameters.keySet())
              name.append(';').append(param).append('=').append(QuotedStringTokenizer.quoteIfNeeded(_parameters.get(param),";="));
          return name.toString();
      }
  
      public void onFrame(byte flags, byte opcode, Buffer buffer)
      {
          // System.err.printf("onFrame %s %x %x %d\n",getExtensionName(),flags,opcode,buffer.length());
          _inbound.onFrame(flags,opcode,buffer);
      }
  
      public void close(int code, String message)
      {
          _inbound.close(code,message);
      }
  
      public int flush() throws IOException
      {
          return _outbound.flush();
      }
  
      public boolean isBufferEmpty()
      {
          return _outbound.isBufferEmpty();
      }
  
      public void addFrame(byte flags, byte opcode, byte[] content, int offset, int length) throws IOException
     {
         // System.err.printf("addFrame %s %x %x %d\n",getExtensionName(),flags,opcode,length);
         _outbound.addFrame(flags,opcode,content,offset,length);
     }
     
     public byte setFlag(byte flags,int rsv)
     {
         if (rsv<1||rsv>3)
             throw new IllegalArgumentException("rsv"+rsv);
         byte b=(byte)(flags | __mask[rsv]);
         return b;
     }
     
     public byte clearFlag(byte flags,int rsv)
     {
         if (rsv<1||rsv>3)
             throw new IllegalArgumentException("rsv"+rsv);
         return (byte)(flags & ~__mask[rsv]);
     }
 
     public boolean isFlag(byte flags,int rsv)
     {
         if (rsv<1||rsv>3)
             throw new IllegalArgumentException("rsv"+rsv);
         return (flags & __mask[rsv])!=0;
     }
     
     public String toString()
     {
         return getParameterizedName();
     }
 }